Abstract: The quality problem of uneven-colored of tomato fruit is taken as the breakthrough point for a teaching experiment by using the problem-based learning method. Students were guided to propose the possible environmental factors which affected fruit colour change. And then, they were encouraged to put forward a reasonable hypothesis to explain the reason of uneven-colored fruit. According to the assumption, the teacher helped students to design a comprehensive experiment, including different temperatures treatment combined with different light intensities treatment. The students were guided to confirm that high temperature inhibited the level of lycopene synthesis gene to block the lycopene accumulation, which resulting in an uneven fruit coloring, through the results of fruit phenotype observation, chlorophyll/lycopene content, fruit firmness and gene expression. Through this experiment, students could really feel the close relationship between agricultural production and scientific research, and realize the importance of theory guiding practice. Therefore, PBL combined with the agricultural production plays an important role in cultivating students’ ability of integrating multi-disciplinary knowledge, students’ scientific thinking, and innovative research ability.

Key words: plant physiology, tomato fruit, uneven-colored, comprehensive experiment, problem-based learning